Quick-acting hydraulic jack



A ril 3, 1962 P. .D. FRIESEN QUICK-ACTING HYDRAULIC JACK Filed Jan. 19, 1959 INV EN TOR. Pezisr Z2 ih'eaeiz' BY M WW United States Patent C) 3,028,142 QUICK-ACTING HYDRAULIC JACK Peter D. Friesen, New Westminster, British Columbia, Canada, assignor to Modern Hydraulics, Inc., West Chicago, 11]., a corporation of Illinois Filed Jan. 19, 1959, Ser. No. 787,507 1 Claim. (Cl. 254--1) This invention relates to a quick-acting hydraulic jack particularly adapted for use in raising buildings, but which may be used for any other desired purpose.

This application is a continuation-in-part of my earlier filed, copending application, Serial No. 588,276, filed May 31, 1956, now abandoned.

An object of the present invention is the provision of a jack which may be quickly put into position and which will start taking or lifting the load the moment it is operated.

Another object of the invention is the provision of a hydraulic jack particularly well adapted for use in confined spaces.

A more detailed object of the invention is to provide a jack having a base adapted to be suitably supported and having an opening therethrough, a jack cylinder extending through the opening in the base and adapted to be vertically adjusted relative thereto, a lifting ram sli-dable in and projecting from the upper end of the jack cylinder, and hydraulic means for actuating the ram within the cylinder.

Another object of the invention is to provide a jack .of the character described wherein a lifting head is carried by the ram and is vertically adjustable relative thereto.

Certain other objects of the invention will, in part, be obvious, and will in part appear hereinafter.

As stated above, this jack is designed particularly for lifting buildings. When it is desired to lift a building off its foundation, numerous jacks are set up under it in order to raise it evenly so as not to strain the structure or crack plaster or windows therein. Hydraulic jacks are usually used for this purpose. However, it is necessary to set each jack so that it starts to take or lift the load at the same time as all the other jacks. This usually entails considerable moving around to operate the numerous jacks. Prior to this invention, it was very difficult to tell when each jack had been raised sufliciently to start taking the load.

The present jack is so constructed that it may be very quickly set up and adjusted to a position where it will start taking the load as soon as it is operated. As jacks used for lifting buildings are often placed on uneven ground, this is very helpful. It saves the operator or operators from moving from one jack to another many times before the jacks are operated to start lifting the load. When the head of a jack is raised by hydraulically operating the jack itself, it is difiicult to determine when it has reached the point where it starts to lift the load. The jack disclosed herein may be set up on suitable supporting members and instantly adjusted so that its lifting head is quickly brought into engagement with the load without the necessity of hydraulically operating the jack. With this arrangement, the jack starts to lift the load as soon as it is hydraulically operated.

For a more complete understanding of the nature and scope of the invention reference may now be had to the accompanying drawings wherein:

FIG. 1 is a side elevational view, partially in vertical section, showing a preferred embodiment of the jack set up for operation;

FIG. 2 is an end elevational view of the jack shown in FIG.1;

FIG. 3 is a top plan view of the jack shown in FIGS. 1 and 2; and

FIG. 4 is a perspective view of one of the jack cylinder supporting plates.

Referring to FIGS. 1 to 3 inclusive of the drawings, a quick-acting hydraulic jack, indicated generally at 10, includes'a base 11 which is preferably in the form of a truncated pyramid, and has a vertically extending opening 12 disposed centrally thereof. A jack cylinder 15 extends through the opening 12 in the base 11 and is movable vertically relative thereto. Although it is not absolutely necessary, it is preferable to provide a sleeve 16 which depends from the base 11 in alignment with the opening 12 thereof so that the jack cylinder 15 extends through the sleeve, as clearly shown in FIG. 1.

The jack cylinder 15 is provided with a plurality of external grooves or notches spaced vertically thereon in rows on opposite sides of the cylinder 15. In the embodiment of the invention shown in the drawings, the notches are in the form of annular grooves 19 that extend completely around the cylinder, each groove 19 being spaced vertically or longitudinally of the cylinder 15 relative to the grooves adjacent thereto.

The jack cylinder 15 is provided with all of the usual elements normally associated with a hydraulic jack cylinder and which are necessary for the operation thereof. As these elements do not form part of the present invention, in general they have been omitted for the sake of clarity. However, a ram 34 is slidable in the cylinder 15 and projects from the upper end 35 thereof. Although the outer end 36 of the ram 34 may bear directly against the load, it is preferable to provide a head 38 extensibly mounted on the outer end of the ram 34 and adjustable vertically or longitudinally of the ram 34. In the embodiment shown in the drawings, the ram 34 is provided with an internally threaded socket 40 in its outer end, and a shaft 41 is adjustably threaded in the socket 40 and extends outwardly therefrom in alignment with the ram 34. The lifting head 38 is in the form of a cap fitting over the outer end of the shaft 41 and is connected to the latter by a pin 42 which extends through the head 38 and the shaft 41. A fluid conduit 39 is shown connected to the lower end of the jack cylinder 15, the other end of which conduit is adapted to be connected to a suitable source of fluid pressure.

The upper surface of the base 11 is provided with a horizontally extending guideway or slideway 43 which is somewhat undercut along its opposite edges, as indicated at 44. In order to support the jack cylinder 15 relative to the base 11, a pair of plates 46 are slidably confined one in each end of the guideway 43. The inner edge of each of the plates 46 is provided with a generally semicircular recess 49, FIG. 4. The plates 46 are adapted to be slidably moved inwardly and into engagement with one of the grooves 19 in the jack cylinder 15 on opposite sides thereof whereby to support the jack cylinder 15 in any one of a number of vertical positions relative to the base 11. When the plates 46 are in their innermost positions, the inner recessed edges thereof overlap the opening 12 formed in the base 11. It is noted in FIG. 3, that the plates 46 when in engagement with the jack cylinder 15 do not completely encircle the portion of the cylinder groove 19 with which they are engaged.

Means are provided to facilitate movement of the plates 46 into and out of engagement with the grooves 19 of the jack cylinder 15. An elongated slot 52 is provided in each of the plates 46 with each slot extending transversely to the direction of sliding movement of its associated plate 46. A circular disc 54 having a diameter approximately equal to the width of the slots 52 is rotatably disposed in each of the slots 52. Each disc 54 is eccentrically and rotatably mounted on one of two upstanding pins 56 which are secured in the bottom surface of the guideway 43 one at each end thereof. This structural arrangement is best shown in FIG. 1 of the drawings. A handle 58 is integral with or rigidly secured to each of the circular disc members 54.

When the circular discs 54are rotated, by means of the handles 58, relative to the pins 56 upon which they are eccentrically mounted, the plates 46 are slidably moved either toward or away from each other for engagement with or disengagement from one of the grooves 19 formed in the outer surface of the jack cylinder 15.

When it is desired to use the jack 10, the base 11 is placed in a substantially horizontal plane on suitable shoring, such as timbers 60 piled up on opposite sides of the sleeve 16. The timbers 60support the base 11 at a point spaced below a load 62 to be lifted. The jack cylinder 15 is then raised through the opening 12 of the base 11 until its lifting head 38 is positioned as close as possible to the underside of the load 62. The handles 58 of the circular discs 54 are then rotated to shift the two plates 46 inwardly and into engagement Withthe appro-' priate one of the grooves 19 formed in the outer surface of the jack cylinder 15 whereby to rigidly support the jack cylinder 15 in one of many vertical positions relative to the base 111 As viewed in FIG. 3, the left-hand plate -46 is in its innermost cylinder-latching position'and the right-hand plate 46 is in its away position, asshown in full lines. Upon rotating the right-hand handle 58 in a-counterclockwise direction to the broken line position shown, the right-hand plate 46 will be moved-inwardly into its cylinder-latching position.

The shaft 41 may now'be-rotated to raise the lifting head 38 into contact or abutting engagement with the under surface ofthe load 62, as shown in FIGS. 1 and2. The jack is-now ready for operation and as soon as hydraulic fiuid under pressure is supplied thereto, as through the fluid conduit 39, the lifting head38starts to immediately lift'the load 62.

It will be understood that certain changes may be made in the construction or arrangement of thequick-acting' hydraulic jack disclosed herein without departing from the spirit and scope of the invention as defined in-the appended claim.

I claim:

A supporting base adapted to permitprepositioning a hydraulic jack'prior to hydraulic actuation thereof, which jack is characterized by a cylinder having a plurality of pairs of external diametrically opposite notches or grooves spaced longitudinally along its length, a piston slidable in the cylinder, and a lifting ram connected to the piston and slidably extending through the upper end'of the cylinder, said supporting base comprising, a base plate member adapted to be suitably supported beneath a member to be raised, said-base plate member being characterized by a central opening extending vertically therethrough which is slightly larger than the outer circumference of the jack cylinder and by a sleeve portion depending from the base plate member in alignment with said central opening, a guideway formed in the upper surface of said base plate member and extending across said central opening therein, a pair of flat plates slidably disposed in said guideway one on either side of said central opening with each of said plates having a generally semi-circular recess formed in its inner end and a thickness which is less than the dimension of the jack cylinder grooves in: a direction longitudinal of the cylinder, said plates being; slidable between outermost positions in which the inner edges thereof do not extend beyond the edges of said central opening in said base plate member and innermost. positions wherein the inner edges thereof-extend beyond the edges of said central opening for supportingengage ment in a pair of the notches or grooves formed inthe jackcylinder, means defining an elongated slot in each: of said plates with said slots extending transversely to the direction of sliding movement of said plates, a pair: of upstanding pins secured in the bottom surface of the guideway one on either side of said central opening with; each pin extending upwardly through one of said slots: in said plates, a pair of circular discs disposed one in each. of said slots in said plates with the diameters thereof being approximately equal to the width of said slots,. each of said discs being eccentrically and rotatably' mounted .on' one'of said pins whereby rotation of saidi discs provides a camming action which serves to'posi-- tively'slide said plates between their innermost and outermost positions, and manually operable handle'means-assd' ciated with each of said discs to facilitate rotation thereof andsliding movement of said plates betweentheir outer-- most positions and their innermost jack cylinder supporting positions whereby to permit prepositioning the hydraulic jack-vertically relative to said base plate member prior to hydraulic actuation thereof with the upper end of the lifting ram disposed closely adjacent to the member to be raised whereupon hydraulic actuation of' the jack causes substantially immediate lifting of the mem.-

her to be raised.

References Cited in the file of this patent UNITED STATES PATENTS 

